biab/ milling / efficiency help

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bronson

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Fellow Brewers,
On sunday i did a biab (5th one ive done) and my efficiency was shameful .
From my brewers friend .com expected O.G 1.069 based on 60% ( dont laugh it gets worse)
i actually ended up with 1.056 a miserable 45%. (previous brews were around 60%)
Now i was attempting a double ipa so all isn't lost as im still banking a 6% beer so i guess its just a regular ipa.

the question i have is how much of the mill setting transfers to a good efficiency. whats the best gauge to run your grain through.
i told my lhbs that it was for a biab and he said " doesnt matter, its the same as allgrain"..... is this true?

technique.
60min mash
10 mash out
50lt keggle w/ mash master weld less thermometer
gas burner
crash chilled
squeezed grain bag
2lt sparge over bag

any advice would be greatly appriciated.
B.
 

Adr_0

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What was your batch size? 2L sparge doesn't seem enough, and you didn't say easy sort of temp your mash, mash out and sparge temp were.

Am inherent problem with high SG beers is that because of the larger amount of grain, more sugar gets held up in the grain (since there is more grain) so even if you have an awesome mash out and sparge you will have a lower efficiency than a similarbbeer made with less grain. The low efficiency would be even lower if you don't mash out warmeenough and sparge with enough hot water.

Not sure on what sort of gap is good for BIAB but since you are using a very fine bag you are not really concerned with letting husk through into the boil like you are with a manifold/false bottom. So the short add answer is that your LHBS guy is full of sh1t and probably just doesn't want to adjust his mill - yes you can go much finer.
 

fletcher

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biab is notorious for declining efficiency once you start to get higher on the gravity scale. i'd say the milling of your grain is of little concern.

things i do if the beer i'm making is over 1.050 starting gravity are:

1. mash for 90 mins. always.
2. stir the mash occasionally. usually every 30 mins and i give it a temperature check then also.
3. mash out for 10 mins
4. keep some DME or dextrose on hand in case i miss my target by more than about 3 or 4 points.
5. i don't sparge but some people do and say it works well for them.

most often, if under, i'll only be under by 1 or 2 points and i don't bother.

if you've only done that many brews (5 or so), i would consider getting a few more under your belt with a lower starting gravity so you can get a better feel for your system. once your readings are more uniform and expected, start making higher gravity beers. even then, the highest so far i've made was i think 1.072ish from memory. i haven't been bothered with any higher yet but i'm sure there are ways to. you CAN get your grain double-milled but i've not seen any benefit when doing it for myself, or i would all the time.

EDIT: grammar
 

nzefactor

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Hey mate

Trawling through the AHB threads here on grain for BIAB you'll come across guys who are completely fine with normal or standard milled grain and get good efficiency yet at the same time others who struggle and get better results purely from using more finely milled stuff. With all the other variables involved in BIAB mashing I reckon it's definitely a case of each to their own and whatever works, so definitely ask the guy next time to mill the grain twice/a bit finer, see if that helps.

What's you're lagging like for the keggle? Your temp holding relatively steady?
Fletcher and Adr_0 have got good advice: Trying a finer mill + a 90min mash + bloody good stirring + good lagging and your low efficiency situation should hopefully be sorted out.
 

bronson

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Thanks guys,
I will definitely take that on board.
I was thinking that a 90min mash may help,
Im thinking of getting my own mill for Father's Day and i guess like you say rather than jump in the deep end, do a few easy brews and build more experience with my equipment.
I just wanted to ask incase i was oblivious to an easy fix.

thanks again , happy brewing
B.
 

ianh

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Cannot help with the high OG brews.

Whilst basically all my beers are <1.050 OG in my case grinding the grain finer increased my efficiency by 3%. This is based on over 100 brews.

As others have said, 90 minute mash and do a few simple brews to get a feel of your setup.
 

Midnight Brew

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Another option might be a small calcium addition to help with mash ph.
 

Adr_0

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ianh said:
Cannot help with the high OG brews.

Whilst basically all my beers are <1.050 OG in my case grinding the grain finer increased my efficiency by 3%. This is based on over 100 brews.

As others have said, 90 minute mash and do a few simple brews to get a feel of your setup.
If you get good flow/contact with the endosperm, you can get away with a coarse grind. This is why RIMS setups don'trreally want a fine grind: from the beginning of the mash you circulate over the endosperm and you need thehhusk intact as a filter medium

IIf you don't have this circulation/contact from the start of the mash, you will not have a good efficiency.

It sounds like the OP may have had a combination of things. Stirring, higher mash out temp, higher sparge volume would all raise efficiency more than the fine grind, but in this case a coarse grind wouldn't have helped. You need alltthe information when making decisions, not just some.

Speaking of which... What were your temps like?
 

mosto

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I was getting around 60% efficiency, until I changed to a mashout step. This increased my overall mash time to around 90 min and my efficiency is now around 75%. Basically, I mash in, leave it for 60 min, ramp up to around 78c, which takes 10-15 min, sit it at that mash out temp for 15 min, then pull the bag and squeeze while raising to a boil. I bought my mill off a fellow AHBer who had two marks set on the gauge which he said he would run it through the coarser setting first then re-mill through the finer setting. I've only ever ran it through the finer setting and it seems to come out quite fine.
 

bronson

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Adr_0 said:
If you get good flow/contact with the endosperm, you can get away with a coarse grind. This is why RIMS setups don'trreally want a fine grind: from the beginning of the mash you circulate over the endosperm and you need thehhusk intact as a filter medium
IIf you don't have this circulation/contact from the start of the mash, you will not have a good efficiency.
It sounds like the OP may have had a combination of things. Stirring, higher mash out temp, higher sparge volume would all raise efficiency more than the fine grind, but in this case a coarse grind wouldn't have helped. You need alltthe information when making decisions, not just some.
Speaking of which... What were your temps like?
sorry for the late reply,
my mash temp was 67c fluctuating 2c up and down over the hour.
mashout was 77c 10mins.
 

Spiesy

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As others have said, mill settings do play a part.

Wort OG can play an even bigger part , especially when you're dealing with beers over 1060OG. There's a case of diminishing returns with high gravity BIAB beers.

Mash temp, mash ph, mash duration and malt type all play a part as well.

More important than a high efficiency, is a repeatable, consistent efficiency - or more the point, getting what you're aiming for. This will help with recipe formulation and development.
 

bronson

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Gents, just a follow up. Happy Days.
I purchased a malt munched and milled my grain at a much finer grind that my lhbs.
Just a single pass through . I very recently done 2 brews since pulling 71% and one of those being 1/5th rice I boiled on the stove. So I'm pretty chuffed it's looking up for my humble little set up.
Also I know have a thick ( Fibre glass/foil) sleeve I put around my ked during my mash and it holds temp for at least 45 mins. I think this steady constant temp would contribute as well.
Thanks again for your knowledge guys . b
 
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